It went dead as a door knob, today. So, I called Apple and they were, as usual, great help. Don't know what I did to knock it out, but if it happens to you hold down the power button on top and the round button on the bottom, simultaneously, for 15 seconds.
Connect the phone to your computer and follow the restore option. It put everything back the way it was. It's important to sync your phone often with your computer (iTunes).
I'm going to guess the cause of the crash. I may have had too many aps open at one time. Just a guess.
Another piece of advice, write your phone's serial number down where you can get to it without your phone. I got mine from the box, but you can get it from iTunes, as well.
For Verizon users, don't forget to do *228 to update your roaming and new towers. I do it at least once a week and have never been anywhere where I couldn't get service.
I'll leave you with a picture or three of my best (lazy) buddy.